A renewed interest in the Belgian-Congolese past can be observed in both wider society and academic historiography, with colonial health care as one of the central themes. However, its flagship – the institutionalised leprosy care - has never been subjected to a critical postcolonial reflection. By looking into the medical evolution and governance of the Congolese model leprosarium Iyonda (1945-1960), this article takes an innovative approach at leprosy history and broader medical colonial history.

This article investigates the relationship between the debates in Belgium about the climate and the so-called health or insalubrity of the Congo, and the political agendas of the contributors to these debates in the period between the start of the Leopoldian exploration of Central Africa in 1876 and the annexation of the Congo Free State by Belgium in 1908. From the very beginning of this exploration, attention was focused on the climate.